By the early 20th century, Cossack's prospects as a bustling port had sunk and its pearl fishing boom had moved to other waters. The town's impressive stone municipal buildings now stood empty.
One of these was the sturdy customs house and bond store, constructed in 1897 from local field stone and ship's ballast. Designed by George Temple-Poole, it had been built to weather the frequent harsh storms that battered the north-west coast.
In the early 1930s, the Department of Works negotiated the sale of the customs house to Monte Bello Sea Products Limited for £500. The company planned to establish a turtle soup canning factory, prepare dry turtle meat and process turtle by-products for fertiliser. They intended to export the delicacies to meet the demands of the European market.
Western Australian Premier James Mitchell was a vocal advocate for the enterprise. He saw it as a prime opportunity to exploit the north-west's natural resources. After viewing a variety of Monte Bello products, including turtle soup, jelly, oil, turtle meat and fertiliser, he compared the industry to gold mining: 'At best, a mine has a limited life, whereas a fishing enterprise can go on forever’. He later wrote to Prime Minister James Scullin enthusiastically backing the factory.
The Cossack Progress Association also had great faith that the factory would return people and prosperity to the town. In 1933, the association pushed for the reinstatement of postal and financial services to support this predicted new growth in business.
However, the optimism about Cossack's renewal was unfounded – fortunately for the local population of green turtles. Monte Bello Sea Products Limited managed only a few shipments of turtle meat before the company went bankrupt in 1935. The town itself was abandoned less than 15 years later.
